目的:探寻肿瘤低发区胃癌的危险因素和保护因素。
Objective To study malaria control measures and effect in low-epidemic area of malaria.目的探讨疟疾低发地区防治措施及其控制效果。
In the 80's of the 20 century, Macdonald model was used widely in the malaria epidemic area.在20世纪80年代,应用该模型对疟疾暴发流行区进行了广泛研究。